Direct gas-fired oven



Oct. 3, 1950 A. M. SAGE 2,524,272

DIRECT GASFIRED OVEN Filed Aug. 22, 1946 3 Sheets-SheetA 1 IN V EN TOR.

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Oct. 3, 1950 A. M. SAGE DIRECT GAS-FIRED ovEN 3 Sheets-Sheet 2 Filed Aug. 22, 1946 @Q w@ wm, m l|||||l ATToRNEY.

Olct. 3, 1950 A. M. SAGE 2,524,272

DIRECT GAS-FIRED OVEN Filed Aug. 22, 194e S sheets-sheet 5 I N VEN TOR.

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ATTORNEY Patented Oct. 3, 195

DIRECT GAS-FIRED OVEN Albert M. Sage, Belleville, N. J., assignor to Steiner-Ives Co., Newark, N. J., a corporation of New Jersey Application August 22, 1946, Serial No. 692,177

3 Claims. l

This invention relates to heating devices.

An object of -the invention is to provide a high humidity heat generator for the heat treatment of objects in an oven or the like.

Another object of the invention is to provide a direct gas red high humidity heat generator whereby high humidity and comparatively high temperatures can be obtained without creating excess steam pressure.

A further object of the invention is to provide a gun type burner firing a ame into a water jacketed combustion chamber, in which steam thus created in the water jacket is fed into the combustion chamber by passing the same through the flame to be heated therebyland then circulated through an oven or the like.

Still another object of the invention is to provide a heat generator of the type specified, which is adaptable to numerous uses, is simple in design, and highly effective in operation.

Other objects and advantages of the invention will become apparent from the following description of a preferred embodiment thereof as illustrated in the accompanying drawings, and in which,

Figure l is a longitudinal sectional view of a heat generator according to the invention, shown installed in an oven;

Figure 2 is a transverse sectional view taken on line 2--2 of Figure 1;

Figure 3 is an `enlarged longitudinal sectional view cf the heat generator shown in Figure l, but apart from the oven, and with parts broken away Vtodisclose the interior construction;

Figure 4 is a transverse sectional View taken on line 4-4 of Figure 3, and

Figure 5 isa transverse sectional View taken on line `5-5 of Figure 3.

I have found that the apparatus hereinafter described, and its principle of application in accordance with my invention, could be satisfactorily `employed in industrial processes requiring the use of superheated `steam as a heat conveyor, heat transferor `or humidifying agent for the drying and baking of cores, moulds, shapes and other forms of products, formed of sand, gypsum, plastics and other materials, where the elimination of `varying shrinkages in the size and shape of the Afinished products, or the elimination of conditions arising during the drying and baking process tending to cause stresses and strains to develop in the materials being dried and baked, is an important element in the manufacturing process.

@screws `is @what PQ thedmWiP-SS, in. which like reference characters denote similar parts throughout the several views. As shown, there isan oven generally indicated at 2, mounted on legs 4, and including a housing having a bottom member or floor S, side walls l2 and I4, front and rear ,end walls 8 and .10, and a top member or oven roof i6. These members form the oven itself, which `has an .oven chamber I8, one or more of the walls, such as being removable in anysuitable manner, such as by being pivoted or Otherwise, to afford access to the inside of the chamber I 8, where removable racks 2D (see Figure l) may be installed for supporting small articles for treatment in the oven. Larger articles may be supported by removinglone or more of the shelves of the racks, or by removing the racks entirely.

Supportedin the oven housing is a heat generator housing generally indicated at 22, and having a chamber 24 formed by front and rear end walls 26 and 28, side walls 30 and 32, and top member 34, the side and end walls being supported upon the oven housing in any suitable manner, so that the top member I6 of the oven housing forms the floor of the heat generator chamber 24.

Communication between the heat generator chamber 24 and the oven chamber I8 is afforded byl means of openings A36 and 38 formed in the oven roof member I6, near its rear and. front ends respectively. A cylindrical tube or casing 4), `forming a combustion chamber 42 is supported horizontally within the chamber `24 being spaced from the top, bottom and sideinner wall surfaces thereof, and having its forward end 44 supported in contact with the inner `surface of the front endwall 25 of the chamber 24. The rearward end 43 of the casing 4i) is supported by a verticalmember `43 which is spaced from the rearward wall `29 of the chamber 24. The inner walls of the rearward end of the chamber 42 are gradually reduced in inside diameter from location toj52, as seen in Figure 3, the discharge outlet of the combustion chamber 42 being locatedat; `52.

,The `vertical member 48 forms o ne wall of a fan housing within which `is disposed a fan casing 54, with its intake `in coincidence with` the discharge outlet,` 52 of the combustion chamber 42. Its outlet pipe 56 leads downwardly into the hot gas passageway 36 formed in the member I3.

A fan 58 having blades E!) is mounted on a shaft 62 extending rearwardly out through rearward end wall i4, and journaled in appropriate bearings,.not` shown, the fan being driven by means of a motor Gli connected to the shaft 62 by means of a belt 66 extending over pulleys carried on the motor and fan shafts respectively.

It is thus apparent that the rotation of the fan 58 will cause hot gases to be drawn through the combustion chamber 42, and circulated through the hot gas discharge duct 55 and the discharge opening 35, into the oven chamber I8, and thence upward through the forward intake opening 38, and thence through a duct SS which leads from the opening 38 into the forward end of the combustion chamber 112.

A gas burner 'IG having suitable air and gas inlets, is secured with its flame discharge opening 'I2 in registry with an axial opening i4 in the forward end wall of the combustion chamber 42, refractory material 'I6 being supported against the inner surface of the said forward wall, and having a flared axial bore 'I8 in the refractory material to allow passage of the flame BI! and hot gases into the combustion chamber. Flame sources other than a gas burner may also be used.

The greater part of the combustion chamber casing lli? is surrounded by a hollow annular water jacket casing B2 closed at both ends 84 and 86, and having a water chamber 88 for the reception of water 9) therein. Water is led into the water jacket through a water inlet pipe 2 which is connected to an outside source of water through a suitable valve. The water level in the water jacket is shown by means of a glass water level guage Sli (see Figure 4) the upper and lower ends of which are connected into the interior of the water jacket by means of pipes 96 and 93.

A number of direct heating pipes lili! extend longitudinally within the fire chamber 42 so as to be in the path of and thus in direct contact with the flame and hot gases therewithin, the pipes mi) being connected at their ends |02 and Ii into the water jacket by means of appropriate elbows and fittings to permit water from the water jacket to circulate through the pipes IUI). A safety valve, not shown, is connected to the upper end of the pipe ISS which communicates with the interior of the water jacket.

As a result of the hot flame and gases, steam is generated in the water jacket, and the steam is allowed to escape therefrom through a steam outlet pipe 68 connected at its upper end Iiil into the water jacket, the pipe leading the steam past a valve I I2 and through pipe I I4 extending through an opening H6 in duct 58. As best seen in Figure 3, the steam is discharged from pipe I Ill through a nozzle IIB which extends into the combustion chamber 42 so as to allow the steam to escape directly in the path of the flame and hot gases.

The steam thus collects additional heat as it passes through the combustion chamber from left to right as seen in Figure 3, and is then discharged through duct 55 into the oven chamber IB under the influence of the blower fan 53.

As a result, there are obtained high humidity and comparatively high temperatures, which may, as desired, range from about 600 to 800 degrees Fahrenheit, without creating excess steam pressure, this being accomplished by the novel structure and method of superheating the steam by directly projecting it into the path of the hot flame and gases in the combustion chamber. Recirculation of the mixed hot gases and steam is accomplished under the influence of the fan 58 which circulates these products through the oven chamber and upwards through the duct 68 into the combustion chamber, the circulatory flow continuing as long as the burner is in operation.

Suitable flue connections may be made as desired, to draw off hot gases and products of combustion, such as, for example, the one shown at I2@ in Figures 2 and 3, with a damper inserted therein. The outer walls of the oven and the heat generator housing, together with the water jacket and the combustion casing, will preferably be insulated against the escape of heat. The usual controls for temperature, humidity, and other critical factors, will preferably be installed, although they are not illustrated in the drawings.

Although I have described a preferred embodiment of the invention in specific terms, it is to be understood that various changes may be made in size, shape, materials and arrangement without departing from the spirit and scope of the invention as claimed.

Having described my invention, what I claim and desire to secure by Letters Patent is:

l. A direct gas-red oven heating device comprising a housing having a combustion chamber therein with inlet and outlet openings, and having an oven chamber with inlet and outlet openings, ducts connecting the outlet opening of the combustion chamber to the inlet opening of the oven chamber, and connecting the outlet opening of the oven chamber to the inlet opening of the combustion chamber, means for propagating flame and hot gases through said combustion chamber, water jacket means coacting with said combustion chamber for generating steam from heat derived therefrom, duct means for conducting steam from said jacket into said combustion chamber, nozzle means for discharging said steam into said combustion chamber in the path of said flame, whereby said steam is intermixed therewith and superheated, and means for circulating said mixture of hot gases and superheated steam from said combustion chamber into said oven chamber, and back into said combustion chamber.

2. A direct gas-fired oven heating device comprising an oven housing having an oven chamber therein, a heat generator housing having a chamber therein, e, hollow cylindrical combustion casing disposed in said heat generator housing chamber in spaced relation to the inner walls thereof, and having a cylindrical combustion chamber therein, a water jacket surrounding at least a portion of said combustion casing and having a plurality of water pipes connected at each end to said water jacket and extending longitudinally through a portion of said combustion chamber, a gas burner for discharging a flame directly into one end of said combustion chamber, a steam outlet pipe for conducting steam generated in said water jacket by said fiame into the combustion chamber near the inlet for said flame whereby said steam is intermixed there-v with and superheated, ducts interconnecting said combustion chamber and oven chamber, and a fan disposed in the path of the said mixture for circulating it from said combustion chamber into said oven chamber and back into said combustion chamber.

3. A direct gas-fired oven heating device comprising a heat generator housing having a chamber therein, a hollow cylindrical combustion casing disposed in said chamber in spaced relation to the inner walls thereof, and having a cylindrical combustion chamber therein, a water jacket surrounding at least a portion of said combustion casing, and havnga plurality of water pipes connected at each end into said water jacket and extending longitudinally through said combustion chamber, a burner for discharging a hot flame into said combustion chamber whereby steam is generated in said water jacket, a steam outlet pipe for conducting said steam into said combustion chamber, a nozzle on said pipe for discharging said steam into the combustion chamber directly in the path of said ame, whereby the steam is intermixed therewith and superheated, and a fan rotatable in said housing in the path of said mixture for drawing the samel through the combustion chamber and discharging it from said housing, said housing having inlet and outlet openings connectable with apparatus requiring moist heat whereby upon such interconnection the heated mixture may be circulated between said combustion chamber and said apparatus.

ALBERT M. SAGE.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 35,276 Fleury et al May 13, 1862 664,751 Hollingsworth Dec. 25, 1900 1,432,248 Hirt Oct 1'7, 1922 1,522,914 Schumacher J an. 13, 1925 1,564,566 Harris Dec. 8, 1925 1,749,451 strong Mar. 4, 1930 1,957,932 Berolzheimer et al. May 8, 1934 

